This proposal represents the second phase of an STTR partnership involving Intuitive Surgical Systems and Johns Hopkins University. Phase I demonstrated the feasibility and promise of integrating laparoscopic ultrasound (LUS) capability into daVinci. Phase II will develop a complete, integrated application environment and testbed surgical applications for LUS-guided liver surgery. Our general goal is to provide the image quality and access of "open" ultrasonography in a minimally-invasive environment, while also improving the surgeon's ability to do ultrasound-guided procedures. The Phase II system will provide a realistic evaluation of the potential of an LUS-capable daVinci system for hepatic surgery as well as evaluation of the design choices and trade-offs in the functions developed. Phase II has 3 specific aims: Specific Aim 1: Develop functional capabilities required for LUS-assisted robotic surgery. We will extend the Phase I architecture to improve robustness, flexibility, and suitability for evaluation. Other functional enhancements include an articulated robotic LUS probe, prototype biopsy and ablation tools, "virtual fixtures" and improved semi-automated behaviors for ultrasound imaging and targeting of lesions, LUS visualization capabilities integrated into the daVinci user interface, as well as other significant enhancements to the interface permitting the surgeon to interact with LUS system, images, and other functions of the system. Specific Aim 2: Produce an Integrated Robotic System for LUS-Assisted Hepatic Surgery. We will combine these capabilities to produce a system suitable for in-vivo testing of 3 hepatic procedures: 1) assessment (staging) to locate and measure tumors; 2) Needle placement for biopsy/ablation; and 3) resection of small tumors. In each case, the goal is to combine the fundamental capabilities developed in Aim 1 with sufficient application-specific tooling and software to provide necessary clinically relevant context for development and to support the evaluations proposed in Aim 3. Specific Aim 3: Evaluate the effectiveness of the overall system and specific functions for hepatic surgery through in-vivo evaluations and ex vivo phantoms. A successful Phase II will provide the foundation of a product that will enable surgeons to perform US-guided hepatic procedures in a minimally invasive manner with the image quality and dexterity currently available with open laparotomies. This has the potential to reduce morbidity, and improve efficacy and efficiency for liver cancer treatment. [unreadable] [unreadable]